A130775 a(1) = 0; for n > 1: a(n) = 2*(prime(n)-1)!/(prime(n)+1).

0, 1, 8, 180, 604800, 68428800, 2324754432000, 640237370572800, 93666727314800640000, 20325889640780924033433600000, 16578303738261941164769280000000

Offset

1,3

Links

Table of n, a(n) for n=1..11.

Mathematica

Join[{0}, Table[2*(Prime[n] - 1)!/(Prime[n] + 1), {n, 2, 15}]] (* Stefan Steinerberger, Jul 16 2007 *)

Crossrefs

Sequence in context: A317486 A360340 A060593 * A332118 A261825 A203359

Adjacent sequences: A130772 A130773 A130774 * A130776 A130777 A130778

Keyword

easy,nonn

Author

Giovanni Teofilatto, Jul 14 2007

Extensions

More terms from Stefan Steinerberger and Robert G. Wilson v, Jul 16 2007

Status

approved